Program Particulars

(02:00–02:56) Music Element

Front page of Erasmus Darwin's Zoonomia(Reproduced by permission of the Syndics of Cambridge University Library)

(02:10) Son and Grandson of Physicians

Charles Darwin's grandfather, Erasmus, was a revered scientist in his own right. He is best-known for his 1801 four-volume work, Zoonomia; or, the Laws of Organic Life, in which he put forward the notion of evolution. Other intellectuals had posited similar proposals, but Charles Darwin was the first to conduct thorough observations and to amass enough evidence to lead to the discovery of the mechanism of evolution: natural selection.

Starting in 1837, Darwin began the first of a series of private notebooks in which he could work out his ideas and comment on contemporaries he was reading at the time. He codified them to track his work. The Red Notebook and Notebook A dwelled mainly on geology, Notebooks B through E focused on transmutation and natural selection, and Notebooks M and N dealt with metaphysical topics, which were the only ones of Darwin's notebooks that he marked as "private" on the inside covers.

In the first of his Transmutation Notebooks, Notebook B, Charles Darwin opens with an exploration of his grandfather's evolutionary ideas by paraphrasing or citing passages from Zoonomia and then using them forms his own work, as on pages 3 and 4:

We see living beings. the young of living beings, become permanently changed or subject to variety, according to circumstance,— seeds of plants sown in rich soil, many kinds, are produced, though new individuals produced by buds are constant, hence we see generation here seems a means to vary. or adaptation.— Again we believeknow in course of generations even mind & instinct becomes influenced.— child of savage not civilized man.—birds rendered wild through generations, acquire ideas ditto. V. Zoonomia.—

On Being has selected specific pages from many of these notebooks as part of an interactive online feature. You can see images of the actual documents and read the transcribed passages. And, if you'd like to understand the larger context of each one of these pages, listen to David Kohn (mp3, 5:19) explain what the passages mean, the history and events surrounding these thoughts, and where Darwin eventually takes these ideas.

(02:22) The Protestant Reformation

The Reformation was a series of movements within the Western Christian church that took place in the 16th century. During this period, a variety of Christian factions in Western Europe protested and questioned the doctrines and practices of the Roman Catholic Church, which ultimately led to the establishment of Protestant denominations.

In continental Europe, Martin Luther, an Augustinian friar, is commonly known for his protestation of the selling of indulgences and his stand as a reformer. Luther gained notoriety for his Ninety-Five Theses. The ideas contained in this document gave impetus to the Reformation. The French reformer John Calvin wrote his Institutes of Christian Religion in exile in Switzerland and established Geneva as a Protestant haven. For the remainder of his life, Calvin stood as the dominant figure in a Geneva that became a point of refuge for persecuted Protestants from all over Europe. King Henry VIII triggered the movement in England when he split with Rome over seeking an annulment.

(2:00) Music Element

Map of the route of the five-year voyage of H.M.S. Beagle(Reproduced by permission of the Syndics of Cambridge University Library)

(02:65) Five-Year Journey of H.M.S. Beagle

The primary mission of the Beagle was to map the coastline of southern South America and take oceanographic measurements. Darwin was not on the Beagle as the ship's naturalist but as a private citizen. While on board, he observed and chronicled almost everything he saw in Nature. He collected specimens of plants, animals, fossils, and rocks; wrote about geological events; recorded meteorological phenomena; and made sociological observations of indigenous peoples.

The Beagle was a rather small ship, measuring 90 feet in length. It carried 74 people, including the captain, Robert Fitzroy. The original voyage was planned to take two years but was extended to five years, which ended in 1836. The ship circumnavigated the globe reaching South America, New Zealand, Australia, South Africa, and back to Brazil before returning to England. But, whatever happened to the Beagle itself?

(03:10) Reading from the Origin of Species

Darwin published his conclusions on the mechanism for evolution in his 1859 On the Origin of Species by Natural Selection; Or the Preservation of Favoured Races in the Struggle for Life. Charles Darwin had long been thinking about and began writing an extensive, multi-volume work on the theory of natural selection in species development in 1856. Alfred Russel Wallace (1823–1913), a naturalist who was working on the island of Ternate in the Moluccas, mailed Darwin a letter on March 9, 1858. In the letter, Wallace addressed the concept of "survival of the fittest."

Darwin received the letter on June 18, 1858, and immediately wrote the geologist Charles Lyell:

Some year or so ago, you recommended me to read a paper by Wallace in the Annals, which had interested you & as I was writing to him, I knew this would please him much, so I told him. He has to day sent me the enclosed & asked me to forward it to you. It seems to me well worth reading. Your words have come true with a vengeance that I should be forestalled. You said this when I explained to you here very briefly my views of "Natural Selection: depending on the Struggle for existence."—I never saw a more striking coincidence. If Wallace had my M.S. sketch written out in 1842 he could not have made a better short abstract! Even his terms now stand as heads of my Chapters. Please return me the M.S. which he does not say he wishes me to publish; but I shall of course at once write & offer to send to any Journal. So all my originality, whatever it may amount to, will be smashed. Though my Book, if it will ever have any value, will not be deteriorated; as all the labour consists in the application of the theory. I hope you will approve of Wallace's sketch, that I may tell him what you say.

A week later he wrote Lyell again:

I am very sorry to trouble you, busy as you are, in so merely personal an affair. But if you will give me your deliberate opinion, you will do me as great a service, as ever man did, for I have entire confidence in your judgment & honour.— I should not have sent off your letter without further reflexion [sic, reflection], for I am at present quite upset, but write now to get subject for time out of mind. But I confess it never did occur to me, as it ought, that Wallace could have made any use of your letter. There is nothing in Wallace's sketch which is not written out much fuller in my sketch copied in 1844, & read by Hooker some dozen years ago. About a year ago I sent a short sketch of which I have copy of my views (owing to correspondence on several points) to Asa Gray, so that I could most truly say and prove that I take nothing from Wallace. I should be extremely glad now to publish a sketch of my general views in about a dozen pages or so. But I cannot persuade myself that I can do so honourably. Wallace says nothing about publication, & I enclose his letter.—But as I had not intended to publish any sketch, can I do so honourably because Wallace has sent me an outline of his doctrine—I would far rather burn my whole book than that he or any man should think that I had behaved in a paltry spirit. Do you not think his having sent me this sketch ties my hands— I do not in least believe that that he originated his views from anything which I wrote to him. If I could honourably publish I would state that I was induced now to publish a sketch (& I should be very glad to be permitted to say to follow your advice long ago given) from Wallace having sent me an outline of my general conclusions.—We differ only, that I was led to my views from what artificial selection has done for domestic animals. I could send Wallace a copy of my letter to Asa Gray to show him that I had not stolen his doctrine. But I cannot tell whether to publish now would not be base & paltry: this was my first impression, & I should have certainly acted on it, had it not been for your letter.— This is a trumpery affair to trouble you with; but you cannot tell how much obliged I should be for your advice.— By the way would you object to send this & your answer to Hooker to be forwarded to me, for then I shall have the opinion of my two best & kindest friends.—This letter is miserably written & I write it now, that I may for time banish [the] whole subject. And I am worn out with musing. I fear we have case of scarlet-fever in House with Baby.-Etty is weak but is recovering.— My good dear friend forgive me.—This is a trumpery letter influenced by trumpery feelings.

After encouragement by several friends, Darwin and Wallace published the first paper on natural selection in the 1858 Journal of the Proceedings of the Linnean Society: Zoology, titled "On the tendency of species to form varieties: and on the perpetuation of varieties and species by natural means of selection."

The book sold out the same day it appeared — November 24, 1859; the publisher limited the first run to 1250 copies. The distilled thinking laid out in the Origin on Species is a culmination of nearly 20 years of the ebb and flow of Darwin's work. Some of the richest records of Darwin's progression of thought are contained in his Red and Transmutation Notebooks opened in the late 1830s.

An expanded version of the passage in the audio broadcast is excerpted from the third chapter of the Origin of Species:

Before entering on the subject of this chapter, I must make a few preliminary remarks, to show how the struggle for existence bears on Natural Selection. It has been seen in the last chapter that amongst organic beings in a state of nature there is some individual variability: indeed I am not aware that this has ever been disputed. It is immaterial for us whether a multitude of doubtful forms be called species or sub-species or varieties; what rank, for instance, the two or three hundred doubtful forms of British plants are entitled to hold, if the existence of any well-marked varieties be admitted. But the mere existence of individual variability and of some few well-marked varieties, though necessary as the foundation for the work, helps us but little in understanding how species arise in nature. How have all those exquisite adaptations of one part of the organisation to another part, and to the conditions of life, and of one organic being to another being, been perfected? We see these beautiful co-adaptations most plainly in the woodpecker and the mistletoe; and only a little less plainly in the humblest parasite which clings to the hairs of a quadruped or feathers of a bird; in the structure of the beetle which dives through the water; in the plumed seed which is wafted by the gentlest breeze; in short, we see beautiful adaptations everywhere and in every part of the organic world.

A page of the 1844 letter in which Darwin first conveys to Hooker his ideas about evolution as if it was like confessing a murder.

(04:38) Like Confessing a Murder

Darwin revealed his views on evolution to very few people outside of his family during his formative years of thought — two of these being the geologist Charles Lyell and the botanist Joseph Hooker. In a January 14, 1844 letter to Hooker, Darwin revealed his ideas about evolution based on the observations he made on the Beagle voyage nearly a decade earlier:

I am almost convinced (quite contrary to opinion I started with) that species are not (it is like confessing a murder) immutable. I think I have found out (here's presumption!) the simple way by which species become exquisitely adapted to various ends."

Darwin's "the simple way" was natural selection.

(06:67–08:18) Music Element

(07:29) Reading from Milton's Paradise Lost

Charles Darwin took four books along on his five-year journey aboard H.M.S. Beagle in the early 1830s: the King James Version of the Bible, the first volume of Charles Lyell's Principles of Geology, Alexander von Humboldt's Personal Narrative, and John Milton's epic poem Paradise Lost :

Let us make now Man in our image, Man In our similitude, and let them rule Over the Fish and Fowle of Sea and Aire, Beast of the Field, and over all the Earth, And every creeping thing that creeps the ground. This said, he formd thee, ADAM, thee O Man Dust of the ground, and in thy nostrils breath'd The breath of Life; in his own Image hee Created thee, in the Image of God Express, and thou becam'st a living Soul.

(10:18–12:12) Music Element

(10:43) Earth as 6,000 Years Old

In the 17th century, two men are credited with coming up with a chronology of the Earth based on the Bible: James Ussher (1581–1656), Archbishop of Armagh (now Northern Ireland), and John Lightfoot, an Anglican clergyman and Hebrew scholar at Cambridge University. In Ussher's 1650 work, Annales veteris testamenti, a prima mundi origine deducti (Annals of the Old Testament, deduced from the first origins of the world), he traced the genealogies in the Bible and calculated that the Earth was created on October 23, 4004 BC at 9 p.m. Whereas, Lightfoot calculated that it occurred sometime around the autumnal equinox in 3929 BC. Ussher also estimated that Adam and Eve were driven from the Garden of Eden on Monday, November 10, 4004 BC.

By Darwin's time, a majority of scientists no longer believed that the planet was only 6,000 years old but thought the date of creation was millions of years earlier. In a February 27, 1837 letter while in Cambridge after his return from the voyage on the HMS Beagle, Darwin wrote to his cousin Caroline:

You tell me you do not see what is new in Sir J. Herschell's idea about the chronology of the old Testament being wrong.— I have used the word Chronology in dubious manner, it is not to the days of Creation which he refers, but to the lapse of years since the first man made his wonderful appearance on this world— As far as I know everyone has yet thought that the six thousand odd years has been the right period but Sir J. thinks that a far greater number must have passed since the Chinese, the [space left in copy], the Caucasian languages separated from one stock. … Yours affectionly, C. Darwin

Darwin would continue to address this issue in the Origin of Species:

The Belief that species were immutable productions was almost inavoidable as long as the history of the world was thought to be of short duration; and now that we have acquired some idea of the lapse of time, we are too apt to assume, without proof, that the geological record is so perfect that it would have afforded us plain evidence of the mutation of species, if they had undergone mutation. But the chief cause of our natural unwillingness to admit that one species has given birth to other and distinct species, is that we are always slow in admitting any great change of which we do not see the immediate steps…. The mind cannot possibly grasp the full meaning of the term of a hundred million years; it cannot add up and perceive the full effects of many slight variations, accumulated during an almost infinite number of generations.

(12:36) Citation from Moore's Writing

The Origin of Species was the last great work in the history of science in which theology was an active ingredient. The word "evolution" did not appear in the text, but Darwin used "creation" and cognate terms over one hundred times. Opposite the title stood a quotation from Lord Bacon about studying God's works as well as His Word, and another by the reverend Master of Trinity College, Cambridge about "general laws" as God's way of governing. On the last page, Darwin rhapsodized about the "grandeur" in his view of life, with nature's "most beautiful and most wonderful" diversity arising from "powers … originally breathed into a few forms or into one."

(13:32) Darwin as an Agnostic

Although Darwin often did not directly respond to admirers, much less people inquiring about his religious views, he did reply to a Dutch man's request in 1873:

A Mon. N.D. Doedes The University Utrecht Holland Confidential April 2 1873 Down, Beckenham, Kent. Dear Sir, I am much obliged for the photograph of yourself and friend. I am sure that you will excuse my writing at length, when I tell you that I have long been much out of health, and am now staying away from my home for rest. It is impossible to answer your question briefly; and I am not sure that I could do so, even if I wrote at some length. But I may say that the impossibility of conceiving that this grand and wondrous universe, with our conscious selves, arose through chance, seems to me the chief argument for the existence of God; but whether this is an argument of real value, I have never been able to decide. I am aware that if we admit a first cause, the mind still craves to know whence it came and how it arose. Nor can I overlook the difficulty from the immense amount of suffering through the world. I am, also, induced to defer to a certain extent to the judgment of the many able men who have fully believed in God; but here again I see how poor an argument this is. The safest conclusion seems to be that the whole subject is beyond the scope of man's intellect; but man can do his duty. With my best wishes for your success in life, dear Sir, Yours faithfully Ch. Darwin

(14:45) Quote from Francis Bacon

The first publication of The Origin of Species in 1859 included two epigrams by Whewell and Bacon at the beginning. The first reprint in 1860 added a quote from Samuel Butler's Analogy of Revealed Religion:

"But with regard to the material world, we can at least go so far as this—we can perceive that events are brought about not by insulated interpositions of Divine power, exerted in each particular case, but by the establishment of general laws." WHEWELL: Bridgewater Treatise. "The only distinct meaning of the word 'natural' is stated, fixed, or settled; since what is natural as much requires and presupposes an intelligent agent to render it so, i.e., to effect it continually or at stated times, as what is supernatural or miraculous does to effect it for one." BUTLER: Analogy of Revealed Religion. "To conclude, therefore, let no man out of a weak conceit of sobriety, or an ill-applied moderation, think or maintain, that a man can search too far or be too well studied in the book of God's word, or in the book of God's works; divinity or philosophy; but rather let men endeavour an endless progress or proficience in both." BACON: Advancement of Learning.

(19:33) Darwin's Experience of Slavery in Brazil

After being in the port of Bahia, Brazil for some time, Darwin becomes somewhat acclimated to his new environs and culture, except when it comes to slavery. On March 12, 1832 — a week after Carnivale festivities began — Darwin writes in his Beagle Diary:

Cap Paget has paid us numberless visits & is always very amusing: he has mentioned in the presence of those who would if they could have contradicted him, facts about slavery so revolting, that if I had read them in England, I should have placed them to the credulous zeal of well-meaning people: The extent to which the trade is carried on; the ferocity with which it is defended; the respectable (!) people who are concerned in it are far from being exaggerated at home.— I have no doubt the actual state of by far the greater part of the slave population is far happier than one would be previously inclined to believe. Interest & any good feelings the proprietor may possess would tend to this.— But it is utterly false (as Cap Paget satisfactorily proved) that any, even the very best treated, do not wish to return to their countries.— "If I could but see my father & my two sisters once again, I should be happy. I never can forget them." Such was the expression of one of these people, who are ranked by the polished savages in England as hardly their brethren, even in Gods eyes.— From instances I have seen of people so blindly & obstinately prejudiced, who in other points I would credit, on this one I shall never again scruple utterly to disbelieve: As far as my testimony goes, every individual who has the glory of having exerted himself on the subject of slavery, may rely on it his labours are exerted against miseries perhaps even greater than he imagines.—

(19:42–20:42) Music Element

(20:02) Reading from Darwin's Field Notebook

Darwin would often carry field notebooks with him when he ventured inland during his five years on the Beagle. His first port of call in South America was Bahia, Brazil in April 1832. Here, Darwin writes in one of his field notebooks while sitting in the forest just before Easter Sunday and right after Palm Sunday — something that James Moore doesn't consider a coincidence:

The corresponding entry in Darwin's Beagle Diary conveys a similar sense of elation:

The contrast of the Palms amongst other trees never fails to give the scene a most truly tropical appearance: the forests here are ornamented by one of the most elegant, the Cabbage-Palm; with a stem so narrow, that with the two hands it may be clasped, it waves its most elegant head from 30 to 50 feet above the ground. — The soft part, from which the leaves spring, affords a most excellent vegetable.— The woody creepers, themselves covered by creepers, are of great thickness, varying from 1 to nearly 2 feet in circumference.— Many of the older trees present a most curious spectacle, being covered with tresses of a liana, which much resembles bundles of hay.— If the eye is turned from the world of foliage above, to the ground, it is attracted by the extreme elegance of the leaves of numberless species of Ferns & Mimosas.— Thus it is easy to specify individual objects of admiration; but it is nearly impossible to give an adequate idea of the higher feelings which are excited: wonder, astonishment & sublime devotion fill & elevate the mind.—

(20:48) Darwin in Tierra del Fuego

While rounding the southern tip of South America, a crew from the Beagle lands in Tierra del Fuego. Darwin is taken aback when he first encounters the indigenous people. In a December 18th, 1832 entry in his Beagle Diary, he writes:

As soon as the boat came within hail, one of the four men who advanced to receive us began to shout most vehemently, & at the same time pointed out a good landing place.— The women & children had all disappeared.— When we landed the party looked rather alarmed, but continued talking & making gestures with great rapidity.— It was without exception the most curious & interesting spectacle I ever beheld.— I would not have believed how entire the difference between savage & civilized man is.— It is greater than between wild & domesticated animal, in as much as in man there is greater power of improvement.— The chief spokesman was old & appeared to be head of the family; the three others were young powerful men & 6 feet high.— From their dress &c &c they resembled the representations of Devils on the Stage, for instance in Der Freischutz.— The old man had a white feather cap; from under which, black long hair hung round his face.— The skin is dirty copper colour. Reaching from ear to ear & including the upper lip, there was a broad red coloured band of paint.—& parallel & above this, there was a white one; so that the eyebrows & eyelids were even thus coloured; the only garment was a large guanaco skin, with the hair outside.— This was merely thrown over their shoulders, one arm & leg being bare; for any exercise they must be absolutely naked.— Their very attitudes were abject, & the expression distrustful, surprised & startled:—

… Their language does not deserve to be called articulate: Capt. Cook says it is like a man clearing his throat; to which may be added another very hoarse man trying to shout & a third encouraging a horse with that peculiar noise which is made in one side of the mouth.— Imagine these sounds & a few gutturals mingled with them, & there will be as near an approximation to their language as any European may expect to obtain.

(21:33) Earthquake in Chile

Darwin recorded in his Beagle Diary on February 20, 1835 while on the west coast of South America:

This day has been remarkable in the annals of Valdivia for the most severe earthquake which the oldest inhabitants remember.— Some who were at Valparaiso during the dreadful one of 1822, say this was as powerful.— I can hardly credit this, & must think that in Earthquakes as in gales of wind, the last is always the worst. I was on shore & lying down in the wood to rest myself. It came on suddenly & lasted two minutes (but appeared much longer). The rocking was most sensible; the undulation appeared both to me & my servant to travel from due East. There was no difficulty in standing upright; but the motion made me giddy.— I can compare it to skating on very thin ice or to the motion of a ship in a little cross ripple.

An earthquake like this at once destroys the oldest associations; the world, the very emblem of all that is solid, moves beneath our feet like a crust over a fluid; one second of time conveys to the mind a strange idea of insecurity, which hours of reflection would never create. In the forest, a breeze moved the trees, I felt the earth tremble, but saw no consequence from it.— At the town where nearly all the officers were, the scene was more awful; all the houses being built of wood, none actually fell & but few were injured. Every one expected to see the Church a heap of ruins. The houses were shaken violently & creaked much, the nails being partially drawn.— I feel sure it is these accompaniments & the horror pictured in the faces of all the inhabitants, which communicates the dread that every one feels who has thus seen as well as felt an earthquake. … I am afraid we shall hear of damage done at Concepcion.

Less than a month later, Darwin describes the toll the earthquake has taken on the church in the town of Concepcion:

The different resistance offered by the two sets of walls is well seen in the great Church. This fine building stood on one side of the Plaza: it was of considerable size & the walls very thick, 4 to 6 ft & built entirely of brick: the front which faced the NE forms the grandest pile of ruins I ever saw; great masses of brick-work being rolled into the square as fragments of rock are seen at the base of mountains.— Neither of the side walls are entirely down, but exceedingly fractured; they are supported by immense buttresses, the inutility of which is exemplified by their having been cut off smooth from the wall, as if done by a chisel, whilst the walls themselves remain standing. There must have been a rotatory motion in the earth for square ornaments placed on the coping of this wall are now seated edgeways.— Generally in all parts of the town arched doorways & windows stood pretty well; an old man however, who was lame, had always been in the custom of running to a certain doorway; this time however it fell & he was crushed to pieces.— … It is a bitter & humiliating thing to see works which have cost men so much time & labour overthrown in one minute; yet compassion for the inhabitants is almost instantly forgotten by the interest excited in finding the state of things produced at a moment of time which one is accustomed to attribute to a succession of ages.

(22:23) Darwin at the Peak of the Andes

In the Keyne's edition of the Beagle Diary, Darwin recounts crossing the continental divide in northern Chile and summiting an Andean peak in late March 1835:

When we reached the crest & looked backwards, a glorious view was presented. The atmosphere so resplendently clear, the sky an intense blue, the profound valleys, the wild broken forms, the heaps of ruins piled up during the lapse of ages, the bright colored rocks, contrasted with the quiet mountains of Snow, together produced a scene I never could have imagined. Neither plant or bird, excepting a few condors wheeling around the higher pinnacles, distracted the attention from the inanimate mass.— I felt glad I was by myself, it was like watching a thunderstorm, or hearing in the full Orchestra a Chorus of the Messiah.

(23:09–26:32) Music Element

(23:14) Reading from Darwin's The Voyage of the Beagle

At the end of his journey in September 1836, Darwin reflects on what he's seen on his travels around the world. The following passage is taken from The Voyage of the Beagle by Charles Darwin:

Among the scenes which are deeply impressed on my mind, none exceed in sublimity the primeval forests, undefaced by the hand of man, whether those of Brazil, where the powers of life are predominant, or those of Tierra del Fuego, where death & decay prevail. Both are temples filled with the varied productions of the God of Nature:— No one can stand unmoved in these solitudes, without feeling that there is more in man than the mere breath of his body.

Attorney Clarence Darrow raises his fist while making a speech during the Scopes Trial of 1925. (Courtesy: Library of Congress)

(26:09) The Scopes Trial of 1925

The Scopes Trial — known as the "Monkey Trial" — was a highly publicized trial in 1925. John T. Scopes, a high school teacher from Tennessee who taught Charles Darwin's theory of evolution, was willingly charged with violating Tennessee's Butler Act — a recently passed law that made it "unlawful for any teacher in any of the Universities, Normals and all other public schools of the State which are supported in whole or in part by the public school funds of the State, to teach any theory that denies the story of the Divine Creation of man as taught in the Bible, and to teach instead that man has descended from a lower order of animals."

William Jennings Bryan argued for the prosecution and Clarence Darrow for the defense. The judge ruled out arguing the constitutionality on the validity of the theory and limited the trial to whether Scopes had taught evolution in a public classroom, which he admittedly had. After eight days of trial and a fiery showdown where Darrow called Bryan to the stand, Scopes was convicted and fined $100. But, shortly thereafter, Scopes' fine was dismissed as being "excessive" by the Tennessee Supreme Court, and the Butler Act law was repealed in 1967.

(26:50–27:34) Music Element

(28:42) Workhouses in Britain

Poor laws in Britain were first enacted in the 14th century and continued into the mid-20th century until the implementation of the National Health Service. Until the passage of the Poor Law Amendment Act of 1834, these statutes tended to be parish-based and selectively applied. Poor people were not forced into workhouses at that time. But the 1834 act rigidly enforced policies affecting the poor, and made the work house the central solution. This shift mirrored a change in attitude towards the poor — from seeing them as victims of their situation — which called for a Christian, charitable response — to holding economically disadvantaged people responsible for their status, a stance rationalized by the belief that the poor were lazy and needed to help themselves.

Covers of two of Darwin's private notebooks on transmutation, Notebooks B and D. (Reproduced by permission of the Syndics of Cambridge University Library)

(29:16) Darwin's Clandestine Notebooks

On Being has selected specific pages from many of these notebooks as part of an interactive online feature. You can see images of the actual documents and read the transcribed passages. And, if you'd like to understand the larger context of each one of these pages, listen to David Kohn (mp3, 5:19) explain what the passages mean, the history and events surrounding these thoughts, and where Darwin eventually takes these ideas.

(29:39) Rev. Thomas Malthus and Poor Law

Thomas Malthus (1766–1834) was an Anglican clergyman who wrote Essay on the Principle of Population in 1798. Malthus observed that plants and animals produce many more offspring than can survive. He concluded that if this can happen to plants and animals who can't control themselves, humanity is capable of overproducing if left unchecked. Malthus suggested that suffering and misery would become a global epidemic because mankind eventually could not provide for the overpopulation. Poverty and starvation were natural outcomes that were built in to provide naturally occurring checks on overpopulation. Malthus believed poverty was divinely inspired and that is was God's way of preventing people from being slothful. Malthus suggested that family size of the lower classes be limited only to the number of children they could support.

Darwin found Malthus' observations useful, but he saw different implications and reached different conclusions. All plants and animals compete for survival in their environments. Those plants or animals who produced the best variation gained a competitive edge that Darwin saw as natural selection. In his 1876 autobiography, Darwin states the importance of reading Malthus' theory in developing his own:

In October 1838, that is, fifteen months after I had begun my systematic inquiry, I happened to read for amusement Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long- continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The results of this would be the formation of a new species. Here, then I had at last got a theory by which to work.

(34:09) Sic Transit Gloria Mundi

On January 31, 1865, Hugh Falconer, a friend of the botanist Joseph Hooker, and Darwin died of a sudden illness at 56. Darwin's initial response to Falconer's death was serene and contemplative. He wrote to Hooker on February 2: "I am much grieved; It will be a great loss to science. What a lot of knowledge of all kinds has perished with him. He was always a most kind friend to me. So the world goes.—"

The next day Hooker responded in a rather gloomy manner: "The inconceivability of our being born for nothing better than such a paltry existence as ours' is, gives me some hope of meeting in a better world. What does it all mean.— When we think what millions upon millions of lives & intellects it has taken to work up to a knowledge of gravity & Natural selection, we really do seem a contemptible creation intellectually & when we feel the death of friends more keenly the older we grow, we do strike me as being corporeally most miserable, for we have no pleasures to compensate fully for our griefs & pains: these alone are unalloyed."

A week later Darwin responded to Hooker's letter conveying a sense of pointlessness about the world and offered little consolation to his friend:

"I quite agree how humiliating the slow progress of man is; but everyone has his own pet horror, & this slow progress, or even personal annihilation sinks in my mind into insignificance compared with the idea, or rather I presume certainty, of the sun some day cooling &p; we all freezing. To think of the progress of millions of years, with every continent swarming with good & enlightened men all ending in this; & with probably no fresh start until this our own planetary system has been again converted into red-hot gas.— Sic transit gloria mundi, with a vengeance.

(34:50–36:28) Music Element

(34:54) Reading from Letter to Asa Gray

Darwin had difficulty with William Paley's idea of a God who acts through Nature. Darwin couldn't believe God designed a particular animal or plant for a singular purpose. In this July 3, 1860 letter to Harvard botanist Asa Gray, Darwin explicitly points out his reasons for rejecting Paley's argument:

One word more on "designed laws" & "undesigned results." I see a bird which I want for food, take my gun & kill it, I do this designedly.—An innocent & good man stands under tree & is killed by flash of lightning. Do you believe (& I really should like to hear) that God designedly killed this man? Many or most person do believe this; I can't & don't.—If you believe so, do you believe that when a swallow snaps up a gnat that God designed that that particular swallow should snap up that particular gnat at that particular instant? I believe that the man & the gnat are in same predicament.—If the death of neither man or gnat are designed, I see no good reason to believe that their first birth or production should be necessarily designed. Yet, as I said before, I cannot persuade myself that electricity acts, that the tree grows, that man aspires to loftiest conceptions all from blind, brute force.

Darwin's famous sketch from Transmutation Notebook B that represents the divergence in his thinking about extinction and adaptation over time. (Reproduced by permission of the Syndics of Cambridge University Library)

(42:00) Reference to Wallace

Charles Darwin had long been thinking about and writing an extensive, multi-volume work on the theory of natural selection in species development. Alfred Russel Wallace (1823–1913), a naturalist who was working on the island of Ternate in the Moluccas, mailed Darwin a letter on March 9, 1858. In the letter, Wallace addressed the concept of "survival of the fittest."

Darwin received the letter on June 18, 1858, and immediately wrote the geologist Charles Lyell:

Some year or so ago, you recommended me to read a paper by Wallace in the Annals, which had interested you & as I was writing to him, I knew this would please him much, so I told him. He has to day sent me the enclosed & asked me to forward it to you. It seems to me well worth reading. Your words have come true with a vengeance that I should be forestalled. You said this when I explained to you here very briefly my views of "Natural Selection: depending on the Struggle for existence."—I never saw a more striking coincidence. If Wallace had my M.S. sketch written out in 1842 he could not have made a better short abstract! Even his terms now stand as heads of my Chapters. Please return me the M.S. which he does not say he wishes me to publish; but I shall of course at once write & offer to send to any Journal. So all my originality, whatever it may amount to, will be smashed. Though my Book, if it will ever have any value, will not be deteriorated; as all the labour consists in the application of the theory. I hope you will approve of Wallace's sketch, that I may tell him what you say.

A week later he wrote Lyell again:

I am very sorry to trouble you, busy as you are, in so merely personal an affair. But if you will give me your deliberate opinion, you will do me as great a service, as ever man did, for I have entire confidence in your judgment & honour.— I should not have sent off your letter without further reflexion [sic, reflection], for I am at present quite upset, but write now to get subject for time out of mind. But I confess it never did occur to me, as it ought, that Wallace could have made any use of your letter. There is nothing in Wallace's sketch which is not written out much fuller in my sketch copied in 1844, & read by Hooker some dozen years ago. About a year ago I sent a short sketch of which I have copy of my views (owing to correspondence on several points) to Asa Gray, so that I could most truly say and prove that I take nothing from Wallace. I should be extremely glad now to publish a sketch of my general views in about a dozen pages or so. But I cannot persuade myself that I can do so honourably. Wallace says nothing about publication, & I enclose his letter.—But as I had not intended to publish any sketch, can I do so honourably because Wallace has sent me an outline of his doctrine—I would far rather burn my whole book than that he or any man should think that I had behaved in a paltry spirit. Do you not think his having sent me this sketch ties my hands— I do not in least believe that that he originated his views from anything which I wrote to him. If I could honourably publish I would state that I was induced now to publish a sketch (& I should be very glad to be permitted to say to follow your advice long ago given) from Wallace having sent me an outline of my general conclusions.—We differ only, that I was led to my views from what artificial selection has done for domestic animals. I could send Wallace a copy of my letter to Asa Gray to show him that I had not stolen his doctrine. But I cannot tell whether to publish now would not be base & paltry: this was my first impression, & I should have certainly acted on it, had it not been for your letter.— This is a trumpery affair to trouble you with; but you cannot tell how much obliged I should be for your advice.— By the way would you object to send this & your answer to Hooker to be forwarded to me, for then I shall have the opinion of my two best & kindest friends.—This letter is miserably written & I write it now, that I may for time banish [the] whole subject. And I am worn out with musing. I fear we have case of scarlet-fever in House with Baby.-Etty is weak but is recovering.— My good dear friend forgive me.—This is a trumpery letter influenced by trumpery feelings.

After encouragement by several friends, Darwin and Wallace published the first paper on natural selection in the 1858 Journal of the Proceedings of the Linnean Society: Zoology, titled "On the tendency of species to form varieties: and on the perpetuation of varieties and species by natural means of selection."

(48:43) Reading from the Origin of Species

It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with Reproduction; inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the external conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less-improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.